Number of nX3 0..2 arrays with values 0..2 introduced in row major order and each element equal to no more than two horizontal and vertical neighbors.

A199650

Number of nX3 0..2 arrays with values 0..2 introduced in row major order and each element equal to no more than two horizontal and vertical neighbors.

Terms

    a(0) =5a(1) =113a(2) =2584a(3) =59212a(4) =1357484a(5) =31120632a(6) =713445976a(7) =16355879648a(8) =374961537040

External references